The invention generally relates to a latch device which permits circuit boards to be stacked in a cabinet while allowing easy removal of the boards from the cabinet either one at a time or in groups of two or more boards.
Devices for stacking circuit boards are well-known in the prior art. Examples of such devices are disclosed in U.S. Pat. Nos. 4,297,769; 3,893,208; 3,852,849; 3,836,703; 3,811,154; 3,777,052 and 3,688,635.
In U.S. Pat. No. 3,836,703 a one-piece spacer support for circuit boards is provided which includes a main body with a lower end comprising flexible locking fingers. The flexible locking fingers are inserted into an aperture in a circuit board where they compress to a diameter smaller than the aperture in the circuit board and then expand once pressed through the aperture to fix the spacer support to a circuit board. The upper end of the main body section has a frame structure with an aperture to allow a second circuit board to be laid over the top end of the spacer support and be similarly locked in place with a second spacer support. Removal of one circuit board from another held together by the spacer supports is difficult since it requires compressing the flexible fingers on each one of the spacer supports and disengaging each of the spacer supports until the circuit board is free.
U.S. Pat. No. 3,893,208 discloses a spacer support, similar to the spacer support disclosed in U.S. Pat. No. 3,836,703, including locking fingers which yieldingly bend when inserted through an aperture in a circuit board to secure one circuit board to another. The locking fingers are formed of "non-return" material and thus do not allow for circuit boards to be engaged and disengaged from one another without the installation of new spacer supports.
None of the prior art devices provide mechanisms for easily removing and replacing circuit boards or allowing for a number of circuit boards to be removed simultaneously.